Fluid filter with modular housing and method of manufacture

ABSTRACT

A fluid filter assembly that includes a filter element that is selected from a plurality of differently sized fluid elements. The filter housing includes an inlet housing section, an outlet housing section and one or more modular housing sections. The modular housing sections are located between the inlet and outlet housing sections and the number of modular housing sections included in the housing is determined by the size of the selected filter element. By employing alternative numbers of the modular housing sections, the filter housing can be constructed for use with each of the differently sized filter elements.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to fluid filters and, more specifically,to a fluid filter having a modular housing.

2. Description of the Related Art

Fluid filters have many manufacturing and processing applications. Forexample, fluid filters are often used in chemical applications, waterapplications, paints and coatings applications, plastics and resinapplications, electronics and semiconductor applications, utilities andpower generation applications, food and beverage applications andpharmaceutical applications.

Conventional fluid filters include a filter housing which receives aremovable filter element which is used to trap and remove particulatesand other matter in the fluid. The filter elements typically take theform of either a filter cartridge or a filter bag. The individualcircumstances of each application will determine the necessary capacityof the fluid filter and conventional fluid filters are manufactured inseveral standard sizes to meet the differing needs of the end user.Fluid filter housings are typically manufactured to hold a particularstandard sized filter element.

In the manufacture of fluid filter housings, there may be some commonfilter housing parts that are used in the manufacture of more than onesize of filter housing, however, there are typically some housingcomponents that define the volume of the filter housing in which thefilter element is placed and which are unique for each individual sizeof filter housing.

Although known fluid filters and methods of manufacture are effective,an improved fluid filter which can be more cost effectively manufacturedis desirable.

SUMMARY OF THE INVENTION

The present invention provides fluid filter having a modular housingthat utilizes common parts to manufacture filter housings havingdifferent capacities.

The invention comprises, in one form thereof, a method of manufacturinga fluid filter. The method includes providing an inlet housing section,providing an outlet housing section and providing a plurality of modularhousing sections having a common configuration. The method also includesidentifying a plurality of differently sized filter elements wherein afilter housing for each of the differently sized filter elements can beassembled by securing a predetermined number of the modular housingsections between the inlet housing section and the outlet housingsection, and wherein the identified plurality of filter elementscorrespond to at least two different predetermined numbers of modularhousing sections. One of the differently sized filter elements isselected and a filter housing is assembled for the selected filterelement by securing the predetermined number of the modular housingsections corresponding to the selected filter element between the inlethousing section and the outlet housing section.

The invention comprises, in another form thereof, a fluid filterassembly that includes a filter element selected from one of a pluralityof differently sized filter elements and a filter housing. The filterhousing includes an inlet housing section, an outlet housing section anda selected number of modular housing sections disposed between the inlethousing section and the outlet housing section. The modular housingsections communicate fluid from the inlet housing section to the outlethousing section with each of the modular housing sections having acommon configuration. The number of modular housing sections differs fordifferently sized filter elements and the selected number of modularhousing sections disposed between the inlet housing section and theoutlet housing section is determined by the selection of the filterelement.

The invention comprises, in yet another form thereof, a fluid filterassembly system that includes a plurality of differently sized filterelements, an inlet housing section, an outlet housing section and aplurality of modular housing sections wherein each of the modularhousing sections have a common configuration. A plurality of fluidfilter housings defining a plurality of differently sized filtercavities are manufacturable from the inlet housing section, the outlethousing section and the plurality of modular housing sections bysecuring alternative quantities of the modular housing sections betweenthe inlet housing section and the outlet housing section. A respectiveone of the plurality of differently sized filter cavities is sized toreceive each of the differently sized filter elements.

An advantage of the present invention is that it provides a fluid filtersystem that provides for the efficient manufacture of fluid filtershaving different sizes using a minimal number of different parts.

BRIEF DESCRIPTION OF THE DRAWINGS

The above mentioned and other features and objects of this invention,and the manner of attaining them, will become more apparent and theinvention itself will be better understood by reference to the followingdescription of an embodiment of the invention taken in conjunction withthe accompanying drawings, wherein:

FIG. 1 is a sectional view of a fluid filter assembly in accordance withthe present invention.

FIG. 1A is a detail view of the fluid filter assembly of FIG. 1 showingthe attachment of the cap.

FIG. 1B is a detail view of the fluid filter assembly of FIG. 1illustrating the method of attaching the filter element.

FIG. 1C is a detail view of the fluid filter assembly of FIG. 1 similarto FIG. 1B and further illustrating the method of attaching the filterelement.

FIG. 2 is a top view of a modular housing section.

FIG. 3 is a sectional view of the modular housing section taken alongline 2-2 of FIG. 2.

FIG. 4 is a side view of a filter basket.

FIG. 5 is an end view of the filter basket of FIG. 4.

FIG. 6 is a top view of the fluid filter cap.

FIG. 7 is a sectional view of the cap taken along line 7-7 of FIG. 6.

FIG. 8 is a top view of the inlet housing section.

FIG. 9 is a side view of the inlet housing section of FIG. 8.

FIG. 10 is a sectional view of the inlet housing section taken alongline 10-10 of FIG. 8.

FIG. 11 is a top view of the outlet housing section.

FIG. 12 is a sectional view of the outlet housing section taken alongline 12-12 of FIG. 11.

FIG. 13 is a perspective view of a filter element.

FIG. 14 is a side view of another fluid filter assembly.

Corresponding reference characters indicate corresponding partsthroughout the several views. Although the exemplification set outherein illustrates an embodiment of the invention, the embodimentdisclosed below is not intended to be exhaustive or to be construed aslimiting the scope of the invention to the precise form disclosed.

DETAILED DESCRIPTION OF THE INVENTION

A modular fluid filter assembly 20 in accordance with the presentinvention is shown in FIG. 1. Filter assembly 20 includes a filterhousing 22 and a filter element 24. Filter housing 22 includes an inlethousing section 26, an outlet housing section 28 and modular housingsections 30. In the illustrated embodiment, filter element 24 is a bagfilter and is located within filter basket 32. Cartridge filter elementsmay also be employed with alternative embodiments of the presentinvention. In the filter assembly 20 illustrated in FIG. 1, two modularhousing sections 30 are disposed between inlet housing section 26 andoutlet housing section 28. An alternative number of modular housingsections 30 may also be used as discussed in greater detail below.

An individual modular housing section 30 is shown in FIGS. 2 and 3. Ascan be seen in these two figures, modular housing section 30 issubstantially cylindrical. An outwardly extending ring 34 is located onthe outer surface of housing section 30 at the longitudinal midpoint ofhousing section 30. Sidewalls 36 of housing section are slightlytapered, having a greater thickness near ring 34 and a smaller thicknessnear the opposing ends 38 of housing section 30. The tapering ofsidewalls 36 facilitates their release from a mold during manufacture ofmodular housing sections 30. The interior surface of sidewalls 36 definean interior cylindrical cavity 40.

Modular housing sections 30 are joined end-to-end and co-axially. Inother words, ends 38 of adjacent housing sections 30 are abuttedtogether during assembly of filter housing 22. The ends 38 of adjacenthousing sections 30 form a fluid tight seal therebetween and the abuttedends 38 may be joined by welding. For example, in the illustratedembodiment, housing sections 30 are formed of polypropylene with 20%glass fiber fill and adjacent housing sections 30 are welded together byinterposing a hot plate between the two ends 38 to be joined and, afterthe ends 38 have been sufficiently heated, removing the plate andbiasing the two ends 38 together so that they are fused together as theycool. Ends 38 may also be joined together by spin welding or any othersuitable method for forming a fluid tight joint.

As described above, opposing ends 38 of each modular housing section 30have the same configuration. Thus, regardless of the number of modularhousing sections 30 located between the inlet housing section 26 and theoutlet housing section 28, the joined housing sections 30 will have twoopposing ends 38 that can be respectively joined to inlet housingsection 26 and outlet housing section 28. Inlet and outlet housingsections 26, 28 each have an assembly interface 42 that takes the formof a cylindrical wall defining an opening 44. Assembly interfaces 42have the same configuration as ends 38 and inlet and outlet housingsections 26, 28. Inlet and outlet sections 26, 28 are also formed ofpolypropylene with 20% glass fiber fill. Consequently, the assemblyinterfaces 42 of inlet and outlet sections 26, 28 can be joined to anend 38 of a modular housing section 30 in the same manner as ends 38 ofseparate modular housing sections 30 are joined together.

Inlet housing section 26 of assembly 20 is shown in FIGS. 8, 9 and 10and includes an access opening 46 located coaxially and opposite opening44. Inlet housing section 26 also includes a threaded inlet opening 48that is joined to a fluid line to receive the fluid that is to befiltered by filter assembly 20. As best seen in FIGS. 8 and 9, a camminginterface for securing cap 56 to inlet housing section 26 includes aseries of cam locking members 50 are located on the outer surface ofgenerally cylindrical inlet housing section 26. Cam locking members 50include a circumferentially extending locking portion 52 and alongitudinally extending stop 54. Cap 56 includes a plurality ofcooperating cam locks 58 that extend circumferentially along the innersurface of cap 56. Cam locks 58 each include an inclined surface 60 anda locking surface 62. When mounting cap 56 to inlet housing section 26,cam locks 58 fit between locking members 50 as cap 56 is longitudinallymounted on inlet housing section 26. Rotation of cap 56 engages eachinclined surface 60 with one of the locking members 50 on inlet housingsection 26. As cap 56 is rotated, locking surfaces 62 are rotated intoengagement with locking portions 52 to tightly engage cap 56 with inlethousing section 26. As cap 56 is further rotated, cam locks 58 engagestops 54 which thereby prevent the over-rotation of cap 56.

A V-shaped gasket 66 (FIG. 1A) is used to form a fluid tight sealbetween cap 56 and inlet housing section 26. Gasket 66 is locatedbetween the inner radial surface 64 of inlet housing 26 that definesaccess opening 46 and cylindrical lip 68 located on cap 56. Gasket 66has an open end 70 that faces the interior volume of inlet housingsection 26 so that the interior of gasket 66 is in fluid communicationwith the fluid within filter assembly 20. Consequently, when pressurizedfluid is present in filter assembly 20 the fluid will bias the twoseparate legs of gasket 66 apart and into sealing contact with interiorsurface 64 and outer radial surface of lip 68 respectively. Inlethousing section 26 includes a vent bore 67 at its upper rim which issealed by gasket 66 when cap 56 is properly seated. If the cap is notproperly seated, liquid will seep from bore 67 when the filter is filledto alert the user.

Filter element 24 is secured by engagement with inlet housing section 26near assembly interface 42. Filter element 24 has a mounting ring 72that is removably mounted to inlet housing section 26 in a snap fitengagement. Ring 72 defines a mounting interface that includes an outerradially extending flange 74 and a generally cylindrical section 76having an outwardly extending annular rib 78 which may be segmented.Ring 72 also includes a second cylindrical mounting section 80 having asmaller diameter. Filter bag 82 is secured to mounting section 80. Inthe illustrated embodiment, ring 72 is formed of polypropylene. Othermaterials, however, such as nylon, polyester or steel may also be usedto form the mounting ring of a bag-type filter element.

Filter bag 82 is a conventional non-woven felt filter bag. Such filterbags may be formed from fibers of a variety of different materials suchas polyester, polypropylene, nylon, nomex, Teflon® or other suitablematerial as is well known to those having ordinary skill in the art.Filter bag 82 has an open end that is attached to mounting section 80 ofring 72 by ultrasonic welds 84. Stitching or other suitable means mayalternatively or additionally be employed to attach bag 82 to ring 72.Bag-type filter elements suitable for use with the present invention arecommercially available from Filter Specialists, Inc. having a place ofbusiness in Michigan City, Ind. For purposes of clarity, filter bag 82is not shown in FIG. 1.

When installing filter element 24 in filter housing 22, filter bag 80 isinserted through access opening 46 and opening 44 into the interiorvolume 40 of modular housing sections 30 until mounting ring 72 engagesinlet housing section 26 adjacent opening 44 to secure filter element 24within assembly 20. The snap-fit securement of mounting ring 72 is bestseen in FIGS. 1B and 1C. FIG. 1B illustrates mounting ring 72immediately prior to its securement. As can be seen in FIG. 1B, outerradial flange 74 forms an acute angle with cylindrical section 76 and asaxially-extending portions 80, 76 of ring 72 are inserted further intoopening 44, radial flange 74 tightly engages inclined shoulder surface86 which surrounds opening 44. An annular groove 88 is located withinopening 44 and rib 78 is seated within groove 88 to secure mounting ring72 in place. As illustrated in FIG. 1C, the seating of rib 78 withingroove 88 forces outer radial flange 74 relatively upwardly as itengages shoulder surface 86 to thereby form a fluid tight seal betweenflange 74 and shoulder surface 86. The dashed line 74 a shown in FIG. 1Cillustrates the position of radial flange 74 in an unbiased condition.

Ring 72 may also be provided with internal handles (not shown) thatextend generally diametrically across ring 72 to allow ring 72 to bemore easily flexed radially inwardly during insertion and removal ofring 72. Such handles are disclosed in U.S. Pat. No. 4,669,167 which ishereby incorporated herein by reference.

A reticulated filter basket 32 may optionally be employed with thepresent invention when using a bag-type filter element. Filter basket 32has a length that corresponds to the length of the filter bag and isused to prevent the filter bag from engaging the interior surface of thefilter housing during filtering operations. Filter basket 32 ispositioned within the filter volume defined by modular housing sections30 and rests upon ribs 90 located within outlet housing section 28.Filter basket 32 has a generally perforated structure defining fluidopenings 92 over the majority of its surface area as best seen in FIGS.4 and 5 with protrusions 94.

During filtering operations, fluid enters filter assembly 20 throughinlet 48 and then passes through ring 72 and opening 44 and into filterbag 82. The fluid then passes through bag 82. As the fluid passesthrough bag 82, the fluid is filtered and particulates removed from thefluid. The filtered fluid then passes through openings 92 in filterbasket 32. The filtered fluid flows between filter basket 32 and theinterior surface of filter housing 22 towards threaded outlet opening 96in outlet housing section 28 where it exits filter assembly 20.

Outlet housing section 28 is shown in FIGS. 11 and 12 and includes threefeet 98 for supporting filter assembly 20 in a vertical orientation.Ribs 90 located within the interior volume of outlet housing section 28are best seen in FIG. 11.

A bag-type filter element 24 is illustrated in FIG. 13. In theillustrated filter element 24, filter bag 82 has a length thatcorresponds to the filter cavity 40 defined by the use of two modularhousing sections 30 as depicted in the fluid filter assembly 20 ofFIG. 1. Dashed lines 82 a and 82 b indicate the length of twoalternatively sized filter elements. In each case, the differently sizedbag-type filter elements would employ a mounting ring 72 having the sameconfiguration whereby each of the bags could be mounted, using thesnap-fit securement method described above, in an inlet housing 26.

As described above, modular housing sections 30 each have the sameconfiguration and are coaxially securable to thereby define a filtercavity 40 having a length that varies depending upon the number ofmodular housing sections 30 joined together. Thus, when it is desired tomanufacture a fluid filter that employs a filter element with a baghaving a length 82 a, the filter housing is constructed using only asingle modular housing section 30 as depicted in FIG. 14. The fluidfilter assembly 20 a shown in FIG. 14 thereby defines a filter cavity 40having a length suited for use with the selected filter element.Similarly, when it is desired to manufacture a fluid filter that employsa filter element with a bag having a length 82 b, the filter housing isconstructed using three modular housing sections 30 to thereby define afilter cavity 40 having an appropriate length.

The present invention thereby facilitates the efficient manufacture offilter housings for a variety of differently sized filter elements. Eachof the filter housings will employ an inlet housing section 26, in whicheach of the different filter elements can be removably mounted, anoutlet housing section 28, and one or more modular housing sections 30.The number of modular housing sections being determined by the size ofthe filter element with which the filter housing is intended to be used.

While this invention has been described as having an exemplary design,the present invention may be further modified within the spirit andscope of this disclosure. This application is therefore intended tocover any variations, uses, or adaptations of the invention using itsgeneral principles.

1. A method of manufacturing a fluid filter, said method comprising:providing an inlet housing section; providing an outlet housing section;providing a plurality of modular housing sections having a commonconfiguration; identifying a plurality of differently sized filterelements wherein a filter housing for each of the differently sizedfilter elements can be assembled by securing a predetermined number ofthe modular housing sections between the inlet housing section and theoutlet housing section, and wherein the identified plurality of filterelements correspond to at least two different predetermined numbers ofmodular housing sections; selecting one of the differently sized filterelements; and assembling a filter housing for the selected filterelement by securing the predetermined number of the modular housingsections corresponding to the selected filter element between the inlethousing section and the outlet housing section.
 2. The method of claim 1wherein the modular housing sections are substantially cylindrical inshape and are coaxially securable and wherein the modular housingsections define a cylindrical filter cavity of variable longitudinallength dependent upon the number of modular housing sections securedbetween the inlet housing section and the outlet housing section.
 3. Themethod of claim 2 wherein the plurality of identified filter elementsinclude a plurality of bag filters defining a plurality of differingfilter lengths.
 4. The method of claim 1 wherein the plurality ofidentified filter elements include a common mounting interface formounting the identified filter elements in the assembled filter housing.5. The method of claim 4 wherein the inlet housing section is detachablyengageable with the common mounting interface whereby the identifiedfilter elements can be removably secured to the inlet housing section.6. The method of claim 1 wherein the modular housing sections haveopposite ends defining a common end configuration and the inlet housingsection and the outlet housing section each define a common assemblyinterface for sealingly engaging the common end configuration.
 7. Themethod of claim 6 wherein any two of the modular housing sections can bejoined end-to-end.
 8. The method of claim 7 wherein the modular housingsections are substantially cylindrical.
 9. A fluid filter assemblycomprising: a filter element selected from one of a plurality ofdifferently sized filter elements; a filter housing, said filter housingincluding: an inlet housing section; an outlet housing section; aselected number of modular housing sections disposed between said inlethousing section and said outlet housing section and communicating fluidfrom said inlet housing section to said outlet housing section, each ofsaid modular housing sections having a common configuration; and whereinsaid number of modular housing sections differs for differently sizedfilter elements, said selected number of modular housing sectionsdisposed between said inlet housing section and said outlet housingsection being determined by said selected filter element.
 10. The fluidfilter assembly of claim 9 wherein said modular housing sections aresubstantially cylindrical and a plurality of said modular housingsections are coaxially disposed between said inlet housing section andsaid outlet housing section.
 11. The fluid filter assembly of claim 9wherein said plurality of differently sized filter elements comprise aplurality of bag filters having bags of differing lengths.
 12. The fluidfilter assembly of claim 9 wherein said plurality of differently sizedfilter elements each have a common mounting interface engageable withsaid filter housing.
 13. The fluid filter assembly of claim 12 whereinsaid common mounting interface is detachably engageable with said inlethousing section.
 14. The fluid filter assembly of claim 9 wherein saidmodular housing sections have opposite ends defining a common endconfiguration and said inlet housing section and said outlet housingsection each define a common assembly interface sealingly engaged withone of said common end configurations.
 15. The fluid filter of claim 14wherein a plurality of modular housing sections are joined end-to-endand disposed between said inlet housing section and said outlet housingsection.
 16. The fluid filter of claim 15 wherein said plurality ofmodular housing sections are substantially cylindrical.
 17. The fluidfilter of claim 9 wherein said inlet housing section defines an accessopening providing access to said modular housing sections and allowinginstallation and removal of said selected filter element therethrough;said fluid filter further comprising: a cap removably securable to saidinlet housing section to sealingly close said access opening, said capand said inlet housing section.
 18. The fluid filter of claim 17 whereinsaid cap and said inlet housing section are securable by a camminginterface.
 19. The fluid filter of claim 17 further comprising aV-shaped gasket sealingly disposed between said cap and said inlethousing section, said V-shaped gasket having an open end incommunication with fluid conveyed within said inlet housing section. 20.The fluid filter of claim 9 wherein said filter housing defines a filteropening, said plurality of differently sized filter elements eachincluding a mounting ring mountable in said filter opening, each of saidmounting rings having a common mounting interface, said mountinginterface including an axially extending portion and a radiallyoutwardly extending flange having a diameter greater than said filteropening, said flange being biased into a fluid tight engagement with aportion of said filter housing surrounding said filter opening bysecurement of said mounting ring in communication with said filteropening.
 21. The fluid filter of claim 20 wherein said axially extendingportion of said mounting ring includes an annular rib extending radiallyoutwardly therefrom, said rib being seatable within an annular groovedefined within said filter opening to thereby secure said axiallyextending portion of said mounting ring within said filter opening. 22.A fluid filter assembly system, said system comprising: a plurality ofdifferently sized filter elements; an inlet housing section; an outlethousing section; a plurality of modular housing sections, each of saidmodular housing sections having a common configuration; and wherein aplurality of fluid filter housings defining a plurality of differentlysized filter cavities are manufacturable from said inlet housingsection, said outlet housing section and said plurality of modularhousing sections by securing alternative quantities of said modularhousing sections between said inlet housing section and said outlethousing section and wherein a respective one of said plurality ofdifferently sized filter cavities is sized to receive each of saiddifferently sized filter elements.
 23. The system of claim 22 whereinsaid modular housing sections are substantially cylindrical and saidmodular housing sections are coaxially securable between said inlethousing section and said outlet housing section.
 24. The system of claim23 wherein said plurality of differently sized filter elements comprisea plurality of bag filters having bags of differing lengths.